Vertically adjustable clamping assembly for a desk or the like



1 0 I G. c. LAMBERT ETAL -3,5-1\7,526

VERTICALLY ADJUSTABLE CLAMPING ASSEMBLY FOR A DESK OR THE LIKE Filed Nov. 14. 1968 INVENTORS GORDON C..LAMBERT, DICK E. SHOEMAYKER a ROBERT c. GANN,

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ATTORNEYS I United States Patent Office 3,517,626 Patented June 30, 1970 Products, Inc., New Castle, Ind., a corporation of Indiana Filed Nov. 14, 1968, Ser. No. 775,623 Int. Cl. A47b 41/00 U.S. Cl. 108144 Claims ABSTRACT OF THE DISCLOSURE A students desk has unitary inverted U-shaped leg members provided with a pair of vertical depressions formed symmetrically about the midpoint of their horizontal portions which are each formed to accommodate a pair of vertically extending spaced parallel columns depending from the book-box. The horizontal portion of the leg member is located inwardly of the spaced parallel columns and the depressions formed in it are preferably formed at a small angle with the vertical such that the tapered leg portions are caused to project slightly outward rather than straight to the floor. Inner and outer clamping brackets are formed to fit around the horizontal portion of the leg member and the vertical parallel columns respectively. The outer clamping bracket has a pair of inwardly extending ends which fit around the horizontal portion of the leg member. The entire assembly is secured tightly together by means of a releasable fastener.

BACKGROUND OF THE INVENTION Classroom desks such as book-box desks customarily have some arrangement for adjusting the height from the floor to accommodate use of the desks in classrooms encompassing a number of grades. For this purpose there is commonly provided a clamping assembly which joins the legs together with a vertically depending support member attached to the desk, for selecting any one of a plurality of desk heights. It is important that such mechanisms securely hold the desk in a predetermined adjusted position over an extended period of use, while not detracting from the appearance of the desk but rather contributing or adding to its appearance. Frequently, such adjusting mechanisms or clamping assemblies have been both complicated and costly to manufacture.

SUMMARY OF THE INVENTION This invention is directed to classroom desks and more particularly to a desk and leg clamping assembly. The desk legs preferably consist of unitary inverted U-shaped legs. A pair of tubes or columns have their upper ends attached to the book-box and extend downwardly in generally parallel spaced apart relation. The horizontal portion of the legs are each formed with a pair of recesses or depressions for selected and interfitting engagement with the inside facing surface of each of the pairs of leg columns. Inner and outer clamping members are provided which partially encircle and interfit about the region adjacent the intersecting columns and horizontal leg portions providing an effective and rigid clamp between these parts, while providing for vertical adjusting movement thereof. One or more of the columns is provided with recesses or indentations, and a suitable protuberance which may be in the form of a screw head or rivet or the like is received in the corresponding legrecess, for mutual selective or interfitting engagement to define the adjusted position of the desk with respect to the leg.

The lower ends of the leg members, in the preferred embodiment, are tapered, and the clamping assemblies of this invention are adapted to support the leg members in such a manner that the outer surface of the tapered leg portions extend substantially vertically with respect to the floor. In this manner, the pigeon-toed appearance common with tapered legs on desks is substantially eliminated.

An outer bracket is formed'with a pair of symmetrical vertically extending arcuate depressions which -fit the outer surfaces of the spaced parallel columns. It also has a pair of perpendicular ends which extend inwardly on either side of the spaced columns. Each of the ends has a horizontally aligned slot for fitting engagement around the horizontal portion of the leg member to prevent rotating moments. An inner clamping bracket is formed as. a semi-cylinder to fit around the inner surface of the horizontal portion of the leg member. When the assembly is fastened together by releasable fastener means, such as a nut-and-bolt, the unitary leg member. and the perpendicular ends of the outer bracket resist buckling and rotating moments. Thus, the assembly is unusually strong. Further, the location of the unitary leg member does not sacrifice a users leg space since the sloping depressions in the leg member causes the legs to be extended outwardly at a small angle with the vertical when the entire assembly is clamped together.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view, from the front, of an open-book-box desk embodying the invention;

FIG. 2 is an exploded view showing the clamping assembly components in perspective;

FIG. 3 is a cross-sectional view taken generally along line 33 of FIG. 1;

FIG. 4 is a vertical cross-sectional view of the assembly taken generally along line 44 of FIG. 3; and

FIG. 5 is a fragmentary elevational view of the desk in FIG. 1 showing the orientation of the tapered leg members with respect to the depending columns.

DESCRIPTION OF THE PREFERRED EMBODIMENT As illustrated in FIG. 1, an open-box desk includes a generally rectangular, horizontal-extending desk top 12 and an open front book-box 14 secured to the underside of the desk top 12-. At each side of the desk 10 are pairs of spaced, parallel tubular columns generally indicated at 16 and 18 which are secured to the desk within the book-box 14 by attachments to the'sides of the book-box, and which extend vertically downward therefrom. Also included at each side of the desk are invertecl U-shaped tubular leg members 20 and 22 located inwardly of their corresponding pairs of columns 16 and 18. The respectively identical clamping assemblies 24 and 25 selectively hold the'leg members 20 and 22 in predetermined positions relative to columns 16 and 18.

As shown in FIG. 2, each inner clamping bracket outer clamping bracket 32, and fastener means including a nut 36 and a bolt 38 cooperate with each leg member 22 and pair of columns 18a and 18b to provide a very rigid clamping assembly 25.

Leg member 22 is comprised of a horizontal portion 40 and downwardly extending tapered leg portions 42 and 44 at either end of portion 40. Floor glides 45 (FIG. 1) may be received on the endsof the legs. A generally traverse bore 46 is located at the mid-point of the horizontal portion 40. On either side of bore 46 are formed a pair of symmetrical arcuate recesses or depressions 48a and 48b which are vertically aligned with columns 18a and 18b. .As shown in FIG. 3, these depressions are formed to conform to the facing surface of the columns 18a and 18b. Any one of the depressions 48a and 48b may be provided 3 with an aperture. For purposes of illustration the aperture 50 is formed in depression 48a. The aperture 50 is formed to accommodate a rivet or screw 51 which, as shown in FIG. 4, penetrates only the facing surface of depression 48a and seats thereon.

A series of vertically spaced notches or indentations 52 are formed in either one of the spaced columns 18a and 18b. For purposes of illustration these indentations are formed in the column which is vertically aligned with depression 48a, namely, column 18a. Each indentation 52, shown in FIGS. 3 and 4 as dimples, is preferably formed as a half-sphere to fit the head of screw 51. It is apparent, however, that any suitable protuberance means may be utilized and that a correspondingly shaped perforation, notch, indentation or the like, is within the scope of this invention.

Inner clamping bracket 30 is formed as a semi-cylinder in order to both fit the inner facing surface of leg member 22 and resist rotating moments. A bore 54 is formed through bracket 30 at its mid-point. For strength, a horizontal built-up rib 56 (FIG. 3) and a vertical built-up rib 58 (FIG. 4) are integrally formed on the outer surface 59 of bracket 30. Both ribs extend radially along the surface 59 from a fiat surface 60 which provides a seating surface for nut 36.

Outer clamping bracket 32 includes a flat center portion 62 having a bore 63 formed therethrough at its mid-point and having a horizontal length approximating the distance between the surfaces of columns 18a and 18b. Bracket 32 further includes a pair of symmetrical arcuate depressions 64a and 64b for selective interfitting engagement with the vertically aligned facing surface of columns 18a and 18b. The lateral ends 66 and 68 of the arcuate depressions 64a and 64b extend perpendicularly to the axis of the depressions 64a and 64b and are preferably provided with horizontally extending slots 70 and 72 for interfitting engagement with the horizontal portion 40 of leg member 22. The ends 66 and 68 are constructed such that the horizontal portion 40, which is positioned behind the columns 18a and 18b, will simultaneously fit into slots 70 and 72 and rest firmly against columns 18a and 18b when the assembly is secured as in FIG. 3. The bracket 32 is also provided with a horizontal built-up rib 74 which gives added strength and provides a seating surface 76 for the head 78 of bolt 38.

As shown in FIG. 3, the outward facing surface of columns 18a and 18b are positioned within depressions 64a and 64b and the inward facing surfaces of columns 18a and 18b are positioned within depressions 48a and 48b, respectively. The interconnection of protuberance 51 and indentation 52 primarily serves to locate but also prevents the horizontal portion 40' of leg member 22 from sliding vertically. When the assembly is secured by drawing the nut 36 tight against the flat surface 60 of inner bracket 30,

the head 78 of bolt 38 will seat on surface 76 and the bolt 38 will project through the bracket 32, between columns 18a and 18b, through the horizontal portion 40' of leg member 22 and through bracket 30. The ends 66 and 68 of bracket 32 will extend laterally around columns 18a and 18b and over-and-uuder approximately half of the circumference of horizontal portion 40, thereby resisting rotating moments.

In the preferred embodiment, the lower ends 80 of the leg portions of leg member 22 are tapered as shown in FIG. 5, and the clamping assembly 25 is adapted to support the leg portion 42, for example, in such a manner that the outer side edge 82 of the tapered lower end 80 will extend generally vertically with the floor so as to. eliminate an otherwise pigeon-toed appearance. The foregoing is accomplished by forming the depressions 48a and 48b in leg member 22 at a small angle with the vertical. The columns 18a and 18b, when brought into interfitting engagement with depressions 48a and 48b, Will abutat right angles with the horizontal. The angle of the depressions 48a and 48b, will nevertheless be reflected in the outward slope of leg portion 42, indicated as angle A in FIG. 4.

It will be obvious that angle A is equal to the angle at which depressions 48a and 48b are formed in leg member 22. It will also be obvious that the bore 46 must be made in leg member 22 at an angle A with the horizontal (FIG. 4) in order to compensate for the rotation of leg member 22 with the vertical when brought into mating engagement with columns 18a and 18b. Angle A preferably corresponds generally to the angle of taper and is chosen such that the center of the floor glides 45 will rest on the floor generally on the line of intersection formed by the intersection of a vertical plane passing through the center line of columns 18a and 18b and the floor. Stated more simply, and as shown in the front view in FIG. 5, floor glides 45 will rest generally directly below the centerline of columns 18a and 18b.

It can thus be seen that the present invention provides a new and improved desk and leg clamping assembly which substantially encircles the vertical support members depending from the desk and cooperates with a unitary leg member to provide a very rigid construction capable of withstanding rough treatment and bending moments over a long period of use. The parts of the assembly are few and are not complicated or costly to manufacture.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention.

What is claimed is:

1. A'vertically adjustable clamping assembly for a desk or the like comprising:

' a pair of spaced generally parallel columns which are secured to the desk and extend generally vertically downward therefrom,

means in at least one of said columns forming a series of vertically spaced indentations,

an inverted U-shaped leg member having a generally horizontal portion defining a pair of symmetrical vertically extending arcuate depressions for interfitting engageemnt with the adjacent surfaces of said column, and being provided with a means forming a horizontally extending protuberance for selective engagement with any one of the said column indentations,

an outer clamping bracket having a pair of symmetrical vertically extending arcuate depressions for selective interfitting engagement with the adjacent surfaces of said columns on a side thereof opposite from said leg member,

a separate and complementary inner clamping bracket formed for interfitting engagement with the facing surface of said horizontal leg portion on a side thereof opposite from said columns,

and means for releasably clamping said brackets to said columns and leg member so that said leg member may be supported in any one of a number of vertically adjusted positions relative to said columns.

2. A vertically adjustable clamping assembly as defined in claim 1 in which said outer clamping bracket further includes a pair of perpendicular inwardly extending ends each defining a horizontally aligned slot for interfitting engagement with said horizontal leg portion when said columns are in mating engagement with said horizontal leg portion v 3. A vertically adjustable clamping assembly as defined in claim 1 in which said protuberance comprises a screw head and in which the vertically spaced indentations have an inner configuration for interfitting engagement with said screw head.

4. The vertically adjustable clamping assembly of claim 1- in which said U-shaped leg member has tapered legs, and in which said horizontal portion thereof is positioned between said clamping brackets with the said tapered legs set outwardly at a small angle to the vertical corresponding generally to the angle of said taper providing an appearance of the legs having generally vertical outer side edges.

5. In a vertically adjustable clamping assembly for a desk or the like,

a. pair of spaced generally parallel columns at each side of the desk which are secured to the desk and extend generally vertically downward therefrom;

means in at least one of the columns in each pair forming at series of vertically spaced indentations;

an inverted U-shaped leg member at each side of the desk having tapered legs and a generally horizontal portion defining a pair of symmetrical vertically extending arcuate depressions formed at a small angle with the vertical corresponding generally to the angle of said taper for interfitting engagement with the adjacent surfaces of said parallel columns and being provided with a means forming a horizontally extending protuberance for selective engagement with any one of the said column indentations;

an outer bracket at each side of the desk having a pair of symmetrical vertically extending arcuate depressions for selective engagement with the adjacent surfaces of said columns on a side thereof opposite from said leg member, and having a pair of perpendicular inwardly extending ends each defining a horizontally aligned slot for interfitting engagement with said horizontal leg portion;

a separate and complementary inner clamping bracket at each side of the desk formed for interfitting engagement with the facing surface of said horizontal leg portion on a side thereof opposite from said columns;

and releasable fastener means at each end of the desk for clamping said brackets to said columns and leg members so that said leg members at each end of the desk may be supported in any one of a number of vertically adjusted positions relative to said pairs of columns and so that said tapered legs may be set outwardly at a small angle in order to provide an appearance of the legs having generally vertical outer side edges.

References Cited UNITED STATES PATENTS 2,368,155 1/1945 Nash 108l48 2,932,510 4/1960 Kravitz 248-423 2,940,806 6/1960 Fields 108144 2,947,586 8/1960 Hoven et al. 108-144 3,058,794 10/1962 Barber 108144 r FRANCIS K. ZUGEL, Primary Examiner Us. CL X.R. 

